Chapter 7: Provision And Use Of Means Of Escape

230. Once a fire has been detected and a warning given, everyone
in the premises should, if necessary, be able to move or be
assisted away from the fire to a place of reasonable safety such as
an enclosed protected stair or another fire compartment from where
they should be able to continue to escape to an unenclosed safe
area beyond the premises. Means of escape is the provision of safe
escape routes for people to travel from any point in a building to
an unenclosed safe area, and includes the measures to maintain
those routes. The number and capability of people present will
influence the assessment of the escape routes. The escape routes
must be sufficient to enable the maximum number of people likely to
use the premises at any time to safely escape.

231. Escape must also be considered from external areas like
enclosed yards and from within perimeter fences provided for
security purposes at outdoor events.

232. Means of escape should be provided both in terms of the
number and capacity of escape routes and in terms of their
protection from fire and smoke. When determining whether premises
have adequate escape routes, a number of interdependent factors
should be considered, including:

the characteristic, number and location of people in the
premises;

the construction of the premises and the potential for fire
and smoke spread;

the fire compartmentation of the premises; and

the time it will take people to escape.

233. The provision of means of escape and the fire protection
given to an escape route will vary depending on the level of risk
within the premises and the occupants. In some premises a single
escape route will be acceptable, in other cases there should be at
least two exits and independent escape routes from each storey of
the premises.

234. In public access premises, persons will generally use
routes with which they are familiar therefore there is advantage if
escape routes are aligned with the general access and circulation
routes.

Escape Routes

235. A room containing more than 60 persons should have at least
two exits, a room with more than 600 should have at least three
exits. But a greater number of exits may be necessary, this will
depend on the actual numbers resorting and travel distance to the
nearest room exit.

236. Even where the number of persons is low, at least two
escape routes may be necessary from:

a storey over 7.5 m in height;

a basement used by the public (other than only toilets);
or

a basement more than 4.5 m deep.

237. In an auditorium that has more than one exit, at least one
exit should be provided not less than two thirds of the distance
from the stage or screen to the back of the room.

238. The direction of travel of alternative escape routes from
any point within a room should:

diverge at an angle of at least 45
o; or

after a single direction of escape (limit as shown in
table 7) then diverge at an angle of at
least 45
o plus 2½
o for every metre travelled in the single
direction.

239. Escape routes should be via a direct and unobstructed
route. Once occupants have left a room they should ideally not have
to pass through another room to reach a protected escape route or a
place of safety. In existing low risk situations, escape may be
from an inner room through an outer room. (See paragraph 258).

240. Where travel distance is to a compartment that does not
itself contain either a final exit or direct access to a protected
stair, then the next adjoining compartments should contain either a
final exit or direct access to a protected stair.

241. An escape route should not be by way of:

a lift (unless specifically designed for evacuation);

an escalator;

turnstiles, other than those with breakout facility opening
in the direction of escape;

a fire shutter which closes automatically in the event of
fire;

a manual sliding door, other than one to which the general
public does not have access;

revolving or automatic doors unless arranged to fail safely
in the outward opening position in accordance with
BS 7036; or

a window.

242. Where children are at a different location in a building
from adults, then the adults may desire to go to the child facility
if the fire alarm sounds. This could involve adults travelling
against the normal direction of escape and this needs to be
considered. Where practicable, relocating the child facility may
avoid this.

243. A clear headroom for escape routes and circulation areas is
at least 2 m, and not less than 1.9 m in a doorway.

244. The width and geometry of escape routes should be
sufficient to facilitate the evacuation method used and for the
number of occupants to escape. From a room or storey with not more
than 100 persons, an escape route width not less than 1000 mm.
Where in excess of 100 persons, 1100 mm may be adequate. At least
1200 mm may be necessary where the room or storey is accessible to
wheelchair users.

245. An escape route will not normally narrow in the direction
of escape but at doorways the width can generally be 150 mm less
than the escape route. Where the number of people using the escape
route is not more than 225, the door width may be at least 850 mm,
and may be 800 mm where the number of people is not more than
100.

246. To assist with evacuation, a door across an escape route
should open in the direction of escape where there are 60 persons
or more (or in factories 10 persons), or where occupants may need
to exit quickly, or the door is a final exit. In other situations
it is good practice for a door to be outward opening if
practicable.

247. The area outside final exit doors should have suitable
underfoot conditions for persons evacuating and pathways so that
persons can move away from the building. Where escape is across
grass or open ground, including from tented structures and open air
locations, the surface should be capable of withstanding the
traffic volumes, taking account of weather conditions and avoiding
the potential for trips and falls.

248. In multi-occupied buildings, escape routes from individual
occupancies should normally be independent of parts in separate
occupancy; people should not have to go through another occupier's
premises to escape as the route may be secured or otherwise
unavailable.

249. In storage areas, the width of gangways between fixed
obstructions such as racking or shelving may not be less than 530
mm. In bulk storage of spirituous liquor, gangways may not be less
than 400 mm.

250. In part of a building with fixed seating consideration
should be given to seating arrangements. Gangway widths and seatway
lengths should allow ease of escape for the numbers present. A
gangway (or exit door) should be provided at each end of a row of
more than 12 fixed seats.

Shopping Centres

251. There will normally be at least 2 directions of travel from
every part of a mall and from every mall-level shop without passing
through a space in single occupation. Each shop with a frontage to
the mall, other than small units, will normally have an alternative
escape route that is not through the mall.

252. The aggregate unobstructed width, in mm, of all escape
routes from a mall should be at least 2.65 multiplied by the
occupancy capacity of the entire centre.

253. Each exit from a mall should be at least 1.8 m wide. Where
occupancy levels will be higher than in other parts of the shopping
centre, a wider exit would be appropriate in those parts. The
entrances used by the public should have the greatest escape route
width as evacuees will tend to use the egress routes with which
they are familiar.

254. Where a service corridor is used for means of escape from a
shop, the width would be based on the total number of persons that
evacuate into the corridor from the largest shop plus an additional
width of 1 m to allow for goods in transit.

Travel Distance

255. There should be a limit on the distance that persons have
to travel to reach a place of reasonable safety. Travel distance is
the distance measured along the actual route of escape (having
regard to the layout) from any point within a storey to the nearest
door giving direct access to either another compartment; a
protected stair; or to a final exit. From a mall-level storey of a
shop in an enclosed shopping centre, travel distance may be
measured to the mall. Travel distance benchmarks are given in
Table 7.

Table 7 - Travel distance benchmarks

Use

Single direction distance(m)

Maximum distance*(m)

Primarily for persons who need more time to evacuate,
such as disabled people, or people with learning difficulties
Boiler room

9

18

Public-access buildings Education and day care High
hazard storage

15

32

Non public-access buildings Enclosed car park

18

45

Within a protected escape route

100

unlimited

* this includes the single direction distance

256. Travel distance benchmarks for occupants of buildings will
not be appropriate for some large or underground travel facilities.
Greater distances may be acceptable in railway stations with a
large dispersal volume for smoke and heat from a fire, and in
underground facilities where combustible materials have been
reduced to a point where there is little to burn.

257. A single direction of escape is travel before there is the
choice of escape routes. See Figures
3,
4 and
5. A single direction of escape may involve
persons moving towards or past a fire, if the fire occurs between
the occupant and the choice of escape routes.

Figure 3 Single direction of escape within a room
before a choice of escape routes becomes available

Figure 4 Single direction of escape out of room
and along a corridor before a choice of escape routes becomes
available

Figure 5 Single direction of escape within a room
before a choice of escape routes, one of which goes through a fire
door into another compartment

Inner Rooms

258. An inner room is a room where access to a circulation area
can only be achieved by passing through an access room (see
Figure 6). A fire could develop unnoticed in
the access room preventing the occupants of the inner room
escaping. The risk to persons in the inner room will be less if the
access room contains limited combustibles and ignition sources; and
travel distance from any point in the inner room to the exit from
the outer room are short. A smoke alarm or automatic smoke detector
in the access room may give an early warning and may be appropriate
where the risk of fire occurring in the access room is high and
cannot be reduced.

Figure 6 Single direction of escape out of an
inner room and through an access room before a choice of escape
routes becomes available

Stairs

Escape stairs

259. To protect escape routes from fire, the normal standard for
escape stairs is for stairs to be enclosed within a fire-resisting
enclosure (creating a protected zone) such that the enclosing
structure between the stair and the rest of the building has
fire-resistance and any door in the enclosing structure is a
self-closing fire door. Each escape stair should have its own
independent final exit.

260. However, an enclosure is not normally necessary for:

an escape stair within a single storey where the difference
in level is not more than 1.8 m;

an external escape stair with a total rise of not more than
1.6 m; or

an escape stair from a gallery where the gallery has:
- an occupancy capacity of not more than 60 or;
- an occupancy capacity of 61 to 100 and at least one
route of escape is by way of a protected zone, an external escape
stair, or another compartment.

261. If the enclosure has an external wall that projects beyond
the face of a building or is set. back in a recess, the route may
be vulnerable should fire break through an adjacent window, door,
or other opening. Radiated heat or flames from the fire may impede
escaping occupants. Therefore an external wall of a building which
makes an angle less than 135
o with the external wall of the enclosure might need to
have fire-resistance.

262. The width of an escape stair should be at least the width
of any escape route giving access to it. A check should be made
that the width of an existing escape stair is suitable for the
persons who would use it and the method of evacuation. Where there
is simultaneous evacuation, the number and capacity of stairs
serving a building needs to be sufficient for the number of persons
to allow the occupants of all storeys to evacuate at the same
time.

263. Where part of a building has only one escape route by way
of an escape stair, if access to the escape stair is by way of a
protected lobby, this will provide an additional barrier to fire
and may afford people additional time to escape. A protected lobby
is where there are two self-closing fire doors between the
adjoining accommodation and the stair.

264. Access by way of a protected lobby is also relevant to a
storey at a height of more than 18 m.

265. Where an escape stair also serves a basement storey, a
self-closing fire door at ground floor level separating the
basement stair enclosure from the stair enclosure serving the rest
of the building will provide improved protection to the means of
escape from any fire that may start in the basement.

266. Ideally, an escape stair (including landings) and the floor
of a protected lobby will be non-combustible. Where an existing
escape stair is combustible, consider the potential for the stair
to be directly affected by fire, such as a fire occurring in an
under-stair cupboard, and the possibility of lining the underside
of the stair with non-combustible material.

267. A small room, reception, cupboard or toilet may be sited
within the enclosure of an escape stair if the fire risk is
considered low and all other parts of the building served by the
escape stair have at least one other escape route.

268. The evacuation speed of people with a mobility disability
can be slow and there may be a space within the protected stair so
that they can wait temporarily until it is safe to use the stair -
a space capable of accommodating a wheelchair and measuring not
less than 700 mm x 1200 mm. These spaces should not be used for
storage. Modern buildings may have an emergency voice communication
system in the temporary waiting space to assist the escape process
and reduce the anxiety of occupants making use of the space.

External stairs

269. An external escape stair may present problems for persons
evacuating a building because people can feel less confident using
an unenclosed stair at a height. For this reason, an external
escape stair may only be suitable where the topmost storey height
is not more than 7.5 m; and the stair is used only by those who can
safely use it. Appropriate weather protection may be necessary to
enable the stair to be used in all weather conditions.

270. An external escape stair should lead directly to a safe
area beyond the premises and should be non-combustible.

271. An external escape stair may be unusable if fire occurs in
the building. External stairs with a rise of more than 1.6 m may
need to be protected against fire from within the building with at
least 30 minutes fire‑resistance.

Escape across Flat Roofs

272. Where the occupants of premises can safely use it, an
escape route may be across a flat roof, and be an alternative
additional provision to another escape route in the premises.

273. The following criteria apply to an escape route across a
flat roof:

be clearly defined, illuminated and guarded with barriers not
less than 1.1 m in height;

have a slip free surface;

have fire-resistance for a distance of 3 m on either side of
the route; and/or

have no unprotected openings from adjacent structures, within
2 m.

Door Fastening

274. It is important that doors necessary for escape be easily
openable while the premises are occupied. Where a door across an
escape route has to be secured against entry, it should be fitted
with a fastening which is readily operated without a key, from the
side approached by people making their escape. Where a door is
operated by a code, combination, card, biometric data or similar
means, it should be capable of being manually overridden from the
side approached by people making their escape. The potential for
persons having to retrace their route during an evacuation to use
an alternative escape route, should also be considered.

275. Push pad devices (to
BSEN
179) are suitable securing devices for outward opening final exit
doors where occupants can be expected to be familiar with the
devices. In other cases, panic exit devices operated by a
horizontal bar (to
BSEN
1125) are suitable.

276. When premises are being used out of normal hours, including
use by community or outside groups, or by security or cleaning
staff, in addition to arranging and controlling access, sufficient
escape routes and exits require to be kept available for the
duration of the occupation.

Electrically powered locks

277. Electrically powered locks can be operated by
electromagnetic or electromechanical means.

278. Electrically powered locks should not be installed on a
door which provides the only route of escape for persons, or which
serves a room or storey with more than 60 persons, or a door on a
fire-fighting shaft.

279. Electrically powered locks should return to the unlocked
position:

On operation of the fire warning system;

On loss of power; and

On actuation of a manual door release unit positioned at the
door on the side approached by people making their escape (where
the door provides escape in either direction, a unit should be
installed on both sides).

280. Access control systems may be in the form of revolving
doors, sliding doors, ticket barriers, or entrance gates. Where
there is no alternative adjacent means of escape, access control
systems across the escape route should in the event of a fire,
power failure, or malfunction, continue to provide a means of
escape without reducing the width by automatically opening and
remaining open; or being readily pushed to the outward open
position by occupants in an emergency.

281. In railway stations, fences and automatic barriers are
often used for revenue protection purposes. The potential impact of
these on escape needs to be assessed and the consequences
considered in respect of congestion, reduction in escape width and
emergency opening arrangements.

282.
BS 7273: Part 4
provides detailed guidance on the electrical control arrangements
for the fail-safe release of powered locks.

Automatic opening doors

283. An internal door may be linked to a motion sensor or other
device so that the door opens automatically to facilitate movement
of occupants. Some devices can be triggered by smoke movement which
may cause a door to open precisely at the time when it should be
closed as a barrier to fire and smoke. These doors should be linked
to the fire warning system so that the automatic opening function
is disabled if the fire warning system is triggered (but still
permitting the door to be manually opened). If the door is a fire
door, the opening mechanism should not reduce the fire-resistance
of the door. When the automatic opening function is disabled
following activation of the fire warning system, the fire door's
normal self-closing function should continue to operate.

284. Automatic opening doors should not be placed across escape
routes unless they are designed in accordance with
BS 7036 and are
either:

arranged to fail safely to outward opening from any position
of opening; or

are provided with a monitored fail-safe system for opening
the door from any position in the event of mains supply failure
and also in the event of failure of the opening sensing device;
and open automatically from any position in the event of
operation of the fire alarm in the fire alarm zone within which
the door is situated.

Powered sliding doors

285. Powered sliding doors often open in response to a motion
sensor. Such a door across an escape route, should be fail-safe and
should open:

on operation of the fire warning system; where
installed;

on loss of power; and

on activation of a manual door release unit positioned at the
door on the side approached by people making their escape (where
the door provides escape in either direction, a unit should be
installed on both sides).

286.
BS 7273: Part 4
contains detailed guidance on the electrical control arrangements
for fail-safe operation of powered sliding doors.

Lighting

287. Escape routes should be provided with lighting to allow
persons to safely use these routes in the event of a fire occurring
or in the event of failure of the normal lighting power supply.

Escape route lighting

288. Premises should be provided with lighting in the escape
routes to the extent necessary to ensure that in the event of an
outbreak of fire, illumination is provided to assist in escape and
to aid staff in implementing the emergency fire action plan.

289. If there are escape routes that are not permanently
illuminated, such as external stairs, then a marked switch or some
other means of switching on the lighting, such as a motion sensor,
should be provided.

Emergency escape lighting

290. Emergency lighting is lighting designed to operate or
remain in operation automatically in the event of a local or
general power failure. The size and type of the premises and the
risk to the occupants will determine whether there is a need for
emergency escape lighting.

291. Emergency lighting can be stand-alone dedicated units or
incorporated into normal light fittings. Power supplies can be
rechargeable batteries integral to each unit or a central battery
bank. Single 'stand-alone' emergency lighting units may be
sufficient in some premises and these can sometimes be combined
with exit or directional exit signs, though the level of general
illumination should not be significantly reduced by the sign.

292. Emergency lighting is described as 'maintained' if it is
permanently illuminated, and 'non-maintained' when it only operates
if the normal lighting fails.

293. In small premises, in which the escape routes are simple
and straightforward, borrowed light may be relied upon to
illuminate escape routes.

294. A system of automatic emergency lighting is likely to be
needed in large complex premises, particularly in those with
extensive occupied basements, sub-surface railway stations or where
there are significant numbers of people. If some escape routes are
internal and without windows, then some form of emergency lighting
may be required. Emergency lighting may be necessary in a room with
more than 60 occupants and escape routes serving such a room and
escape routes in public access buildings which have two storey
exits.

295. A maintained system should be installed in premises such as
cinemas, theatres or nightclubs where the normal lighting can be
dimmed or reduced below the levels required for escape route
identification and illumination while the premises are
occupied.

296. An emergency lighting system provided for escape purposes
may be used to illuminate the following:

297. In the case of a building with smoke control, the units
should be below the smoke reservoir so that it is not rendered
ineffective by smoke filled reservoirs.

298. British standards relevant to emergency lighting systems
are
BS 5266: Part 1 and
BSEN
1838.

Signs and Notices

299. In small simple premises where the locations of escape
routes and fire-fighting equipment are readily apparent then fire
signs may not be necessary.

300. Escape route signs are used to indicate escape routes not
in normal use and are only necessary where there might otherwise be
confusion regarding the route to follow in the event of fire. The
following criteria apply to escape route signs:

they should provide enough information to enable people to
identify escape routes;

where the location of an exit is not obvious, signs with
directional arrows may be provided along the route;

escape route and exit signs should not be fixed to doors as
they may not be visible if the door is open;

signs mounted above doors should be at a height of between 2
m and 2.5 m above the floor; and

signs on walls should be mounted between 1.7 m and 2 m above
the floor.

301. The legibility of an escape sign is determined by the size
of the sign, the level of illumination and the distance over which
it is viewed. Signs should be in pictogram form. The pictogram can
be supplemented by text if necessary to make the sign easily
understood. Guidance on the use of escape route signs is available
in
BS 5499: Part 10.

302. In public access buildings, persons may be unfamiliar with
the location of alternative exits and signs identifying exit
location are important. In shops, the presence of advertising and
customer information or shop dressing needs to be arranged so that
it does not distract from, or obscure escape signs. In storage
premises, escape signs should not be obscured by stored goods. In
places of entertainment and assembly, advertising, information or
other display material should be arranged so that it does not
distract attention from, or obscure escape signs.

303. Signs to indicate the location of non-automatic fire safety
equipment may be necessary if there is any doubt about its
location, such as fire extinguishers that are kept in cabinets or
in recesses. Other signs may also be necessary such as:

'Fire door keep shut' or 'Fire door keep locked shut' on fire
doors;

'Automatic fire door - keep clear';

how to operate the securing devices on doors; and

location of sprinkler stop valve.

304. New safety signs should comply with
BSENISO
7010.

305. Notices are used to provide instructions on how to use any
fire safety equipment and the actions to be taken in the event of
fire. Notices containing details of the emergency fire action plan
specific to the premises should be permanently displayed in
appropriate positions throughout the building. A distinction may be
required between notices that are designed for visitors as opposed
to those for staff.

306. In small premises where there is a limited number of people
and there is no fire warning system, notices may not be
necessary.

307. As well as positioning fire instruction notices on escape
routes adjacent to fire alarm call points, they should be located
where staff frequently assemble in the premises.